Thousands of cyclists hitting the streets at once; it's a ride they call Critical Mass. And now, two months after we first told you about the traffic and safety concerns, Houston police are weighing in on the future of the ride.

The cycists meet at Market Square Park then bike on Houston streets. The Houston Police Department has been helping provide security for the group but now says it can't continue to do so without a cost.

They gather once a month to ride. It's called Critical Mass, and regular participant Ryan Herbert knows some riders can get rowdy.

With up to 2,000 participants each time, Houston police has been sending out officers to help direct traffic. Now, Houston police chief Charles McClelland says it's time for the cyclists to help foot the bill.

"To me, this is no different than a large funeral, a large parade," McClelland said.

Unlike a parade or even the marathon, Critical Mass has no board and no one to get a permit.